Biology 3.1 Flashcards
(16 cards)
Homeostasis
maintenance of stable internal conditions in response to environmental changes
Tissues
groups of similar cells
Epithelial tissues
protective, cover exposed regions of the body, classified by shape such as squamous, cuboidal, columnar, classified by layer
Nervous tissues
conducts signals from nervous system
Connective tissues
provides structure, fibrous, cartilage bone, blood
Muscle tissues
smooth, striated, cardiac
Negative feedback
senses environmental changes to aid with homeostasis, consists of receptor, integrator and effector
receptor
part of negative feedback, detects change in condition beyond tolerable limits
integrator
part of negative feedback, usually the brain, evaluates detected changes and institutes the compensatory adjustment
effector
part of negative feedback, carries out the adjustment
Thermoregulation
control of body temperature by homeostasis, consists of ectotherms and endotherms
Ectotherms
Aka Poikilotherms. Obtain body heat from the environment, basks in sun. Ex. invertebrates, amphibians, reptiles, fish
Endotherms
Aka Homeotherms, generate their own body heat by:
- cooling by evaporation: endergonic reaction turns liquid to gas such as sweating
- warming by metabolism: ex. contracting muscles to produce heat
- adjusting surface area: extremities can become cold and blood flow is adjustable to these areas
Vasodilation
widening of blood vessels to increase blood flow
Vasoconstriction
constricting of blood vessels to limit blood flow
Countercurrent exchange
When blood flows to the extremities, blood moves back to the heart in opposite direction. The warmer blood passes heat to the colder blood
